In poor nations with restricted access to the web or territories without power, for example,many areas in Africa continent don't got sufficient support , there are still obstacles to cross there. So the basic things like internet connection , electricity access etc. Still Bank exist there. But they are following conventional paper work. Still They have not convert the system to online. Both bitcoin and the conventional banking system will exist together for years to come.
This is true, but it's interesting how the technology being somewhat behind could also work in favor of Bitcoin. Check out this story:
http://www.bbc.com/news/world-africa-42582343
I'm working under the assumption that limited infrastructure is one of the reasons why transferring funds across borders is expensive, but Bitcoin seems to solve that problems for at least a couple of people. Bitcoin fees are smaller, and the people won't even have to go through all that banking red tape as a bonus.
Bitcoin can certainly disrupt how the banking system currently operates, but I wouldn't go as far as to say Bitcoin will be the death of it. Bitcoin still has a lot of problems ahead of it, like scaling, volatility, etc.
Yes this factor is alarming for developing countries , like my country. A big amount of money is entering in our country through foreign remittance which makes back the middle man. If there were not back govt could not get much tax , and the quality of the consumer could increase.